BS ISO 4832:2006 pdf free.Microbiology of food and animal feeding stuffs — Horizontal method for the enumeration of coliforms — Colony-count technique.
This third edition of ISO 4832 cancels and replaces ISO 4832:1991 and ISO 5541-1:1986. The main changes are follows:
— the alternative procedure of incubation at 35 °C has been deleted (see 4.2):
— a confirmation test in brilliant green lactose bile broth has been introduced (see 5.4 and 9.4).
Considering the nature of the changes to the previous edition of this International Standard, it is considered that the validation of alternative methods based on ISO 4832:1991 is not affected by this revision.
Because of the large variety of food and feed products, this horizontal method may not be appropriate in every detail for certain products. In this case, different methods which are specific to these products may be used if absolutely necessary for justified technical reasons. Nevertheless, every attempt should be made to apply this horizontal method as far as possible.
When this International Standard Is next reviewed, account will be taken of all information then available regarding the extent to which this horizontal method has been followed and the reasons for deviations from this method in the case of particular products.
The harmonization of test methods cannot be immediate, and for certain groups of products International Standards and/or national standards may already exist that do not comply with this horizontal method. It is hoped that when such standards are reviewed, they will be changed to comply with this International Standard so that eventually the only remaining departures from this horizontal method will be those necessary for well- established technical reasons.
The technique described in this International Standard is more precise than that described in ISO 4831, but does not allow a microbiological examination to be carried out on such a large test portion. It is therefore the preferred method when large numbers of coliforms are present. Moreover, since the definition of “coliforms” adopted in the two documents is different, the microorganisms enumerated are not necessarily the same. For any particular product, the method to be chosen will be specified in the International Standard dealing with that product.
This International Standard gives general guidelines for the enumeration of coliforms. It is applicable to
— products intended for human consumption and for the feeding of animals, and
— environmental samples in the area of food production and food handling,
This technique is recommended when the number of colonies sought is expected to be more than 100 per millilitre or per gram of the test sample.BS ISO 4832:2006 pdf free download.